Several applications of nematic liquid crystal devices have been reported that utilize bistability. This feature is important, since it provides a pronounced memory of the last imprinted ON-OFF state to the resulting display, in the absence of any field.
However, a characteristic of certain of these bistable devices is that a high pretilt angle is required in order to avoid stripe formation. As a result, the devices were constructed using evaporated SiO as the alignment layers. Such a procedure, however, is an elaborate and expensive process.
A more economical approach to liquid crystal device fabrication is the use of polyimide alignment layers. However, stripe formation in the resulting display is always a concern when using standard polyimide alignment layers. It would be desirable, therefore, to provide a liquid crystal device containing liquid crystal material exhibiting bistability which is capable of being economically fabricated, while avoiding stripe formation.